Windmill



UNITED STATES PATENT OFFICE.

HOMER B. SPRAGUE, OF GRANTVILLE, MASSACHUSETTS.

WINDMILL.

SPECIFICATION formingpart of Letters Patent No. 243,169, dated June 21,1881.

Application filed March 16, 1881. (Model.)

To all whom tt may concern:

-Be it known that I, HOMER B. SPRAGUE, of Grantville, in the town ofNeedham, county of Norfolk, and State of Massachusetts, have invented anew and useful Improvement in Windmills, of which'the following is aspecification.

Figure 1 is a rear elevation of the improvement. Fig. 2 is a sectionalside elevation. Fig. 3 is a rear viewof the swivel, enlarged. Fig. 4 isa side view of the swivel, enlarged.

The object of this invention is to furnish self-regulating windmills soconstructed that the sails or vanes will adjust themselves to thevarying force of the wind, so that the drivingwheel will rotate at anearly uniform velocity and with more or less power up to the limitpermitted by the wind and according to the gravity of the weight orforce of the pulling power applied to the cord that draws the sails orvanes into position to catch the wind, as hereinafter stated, whichwindmills shall at the same time be simple in construction, inexpensivein manufacture, strong and durable, and capable of being easilyrset upand of being packed in small compass for storage and transportation.

Similar letters of reference indicate correspondin g parts.

A represents the support for the windmill. This may ordinarily be ahollow iron pipe or tube standing upright, and which may turn on itslower end or upon a flange or collar when thewind changes its direction.To the top of the support A are attached one or two projecting arms,upon which arm or arms B are attached the bearing or bearings on whichrests the horizontal shaft 0. If there is but one arm the other bearingmay rest on the top of the vertical tube or pipe A, which constitutesthe support above named. The said arm or arms Beither rotate freelyhorizontally upon this upright support, according to the veering of thewind, or are firmly fastened to the upright support, in which lattercase they turn with it when there is a change in the direction of thewind.

spokes E maybe attachedacord, rim, or chain, F, to hold said spokesfirmly in proper relative positions. I

' G are the sails or vanes, which are made in triangular, oblong, orother convenient form, and are attached at their sides or at top andbottom directly or by cords, or otherwise to the spokes E or to theouter rim, cord, orchain, F, the other side or edge being unattached, asshown in Figs. 1 and 2. These sails or vanes G can be made of canvas orother suitable flexible material, which construction I prefer, or theymay be made of wood or iron or other suitable rigid material. In thelatter case the sails or vanes G should be hinged to the spokes E or arim by metal straps or other suitable hinges.

To the outer end of each spoke E is attached a pulley or one end of ashort cord or chain, to the other end of which cord or chain is attacheda pulley, over which pulley passes a longer cord, H, which is attachedto the free corner or side of the sail G, which sail is attached byhinges or otherwise, as before de scribed, to the next adjacent radialspoke or to the rim, cord, or chain that connects firmly said spokes.After passing over the pulley before mentioned the said longer cord H,one end of which is attached to the free side or corner of said sail,extends down and passes either directly or over a pulley, to reducefriction, into the rear end of the shaft 0. Or, instead of thisarrangement, several of said longer cords may, at some few inchesoutside the said shaft,be united in one or tied to one cord or chainwhich enters the rear end of the shaft 0.

Inside the shaft (J, which is made hollow to receive the cords soattached to the sails, is a swivel, J, to the rear end of which swivelJthe ends of the cords are fastened, so that when the swivel J is drawntoward the other end of the horizontal shaft 0 the cords are drawn withit, and thereby the sails or vanes are drawn into a position suitable tocatch the wind.

The pulleys at the rear end of the shaft C may be dispensed with, inwhich case the end of the shaft 0 should be made flaring or trumpetshaped,-to form a smooth surface for the cords H to work upon. The shortcords and pulleys near the outer ends of the radial spokes or near thesition.

rim or chain connecting said spokes may also be dispensed with, in whichcase the longer cords H may be attached to or near the ends of theradial spokes, each to each, or to the proper portion of said rim orchain, and then each of said cords H may pass through an eyelet or ring,I, or over a pulley in the free corner or side of the adjacent sail, andthence down toward the rear end of the horizontal shaft (3, as beforestated and as shown in the drawings. With this construction the cords Hand the rear part of the swivel J are carried around by and with thewheel D E F and the shaft 0 in their revolutions.

To the forward or stationary part of the swivel J is attached the end ofacord or chain, K, which may pass over a guide-pulley, L, attached tothe turn-table, or to the upright support A, or to one of the projectingarms B, and when the windmill is to be put in motion the cord has aweight, M, suspended from its lower end or the lower end may be drawndown and made fast to the upright support A or to a spiral spring, so asto give the proper tension. WVhen the mill is to be at rest the cord maybe released by removing the weight or otherwise, so that the sails willbe relaxed and not catch the wind. \Vhen a slight force is required ofthe driving-wheel a light weight is suspended at the lower end of saidcord,'and a heavier weight for a greater force. The cord K may pass downthrough the cavity of the turn-table and the support A, or it may passalong on the outside of the upright pipe or tube A, so that the rotationhorizontally of the turn-table or the revolution of the upright tube orpipe A round its own axis, according to the changes in the direction ofthe Wind, will not unfavorably affect the cord K and the weight M, butwill carry both around in the same relative po- The weight M should beof such gravity and should operate with so little friction as to holdthe cords H more or less taut and the sails G at a suitable angle withthe plane of the spokes E when there is a wind and it is desired to havethe mill working. As the force of the wind increases the pressure of thewind carries the free angle or side of the sails leeward, raising theweight M, so that the sails present less surface to the wind, until in agale the sails take a position nearly or quite at right angles with theplane of the spokes, which arran gement, acting automatically, keeps upthe revolution of the wheel with a force and velocity uniformlyproportioned to the amount of the weight attached. Then, as the velocityof the wind decreases, the weight M draws the sails G forward to catchthe wind, and the wheel continues to revolve as before as long as afairamount of wind is blowing upon the sails. The position of the sailsbeing thus adjusted to the wind by the weight M, the wind-wheel willrevolve at a uniform rate and power however much the wind may vary, andby using a heavier or lighter weight, M, the sails may be adjusted atwill to resist a greater or less force of wind and develop a greater orless power in the mill. I

If desired, the shaft 0 may be made double, consisting of two or moresolid parallel shafts with a sliding swivel partly between the parallelparts and partly outside, the cord from the forward end of the swivelpassing, as before, through a hollow space in the line of the axis ofrotation. In this case the cords attached to the other or rear end ofthe swivel need not pass through the shaft or any part of it, but extenddirectly from the swivel to the pulleys near the outer ends of theradial spokes, and thence to the free corners or sides of the sails; or,after leaving the swivel, they may pass directly through the eyelets orrings at the free corners or sides of the sails, and thence to or nearthe outer ends of the radial spokes, and be made fast there; or,dispensing altogether with said pulleys, eyelets, and rings, the saidsail-cords may pass directly from the rear end of the sliding swivel tothe free angles or sides of the sails and be fastened thereto.

Instead of either of the foregoing arrangements, a single solidhorizontal shaft may be employed, with a slide moving freely upon it, towhich slide the longer sail-cords may be attached directly, the otherends of said cords passing to the pulleys near the ends of the radialspokes, or through the eyelets or rings, or to the free sides or anglesof the sails, to be attached there, as aforesaid. In this case theswivel may be dispensed with and a lever working against the forwardpart of the slide in a groove and moving the slide back and forth may beattached, a cord being made fast to the free end of the lever and aweight suspended by said cord, as may be desired, to operate the leverand the slide and the sails. In this case, too, stiff rods, instead ofsailcords, may pass directly from the slide to the corners or edges ofthe sails, to adjust the latter to the wind.

The shaft 0 is designed to be provided with an eccentric, N, or with acircular wheel with driving-belt or gearing-cogs. lVith the cocentric Nmay be connected the upper end of a pitman, O, or similar device passingdown through the cavity of the turn-table, if a turntable is used, andthrough the support A or passing down alongside the support A andconnecting with the pump or other machinery to be driven.

To the middle or any other part of the spokes E maybe attached a cord,P, ora chain or other device, which may pass around upon the windwardside of the sails G, to prevent the sails from flapping forward orbecoming entangled when the wind suddenly shifts.

With this construction the wind-wheel acts as its own vane to keepitself turned to receive properly the wind, either the upright support Awith all that it sustains turning with the veering of the wind or theturn-table or the supporting arm or arms turning upon IIO the top of theupright support A, so that no In a windmill, the combination, withspokes 10 separate steering-vaneis required. Such vane, E and triangularsails G, of the cords H, shaft however, may be attached, if desired, tothe O, carrying swivel J, and the rings I, as detnrn-table or to. theupright support A, as the scribed. u

case may be, on the leeward side of the whole apparatus HOMER B.SPRAGUE.

Having thus fully described my invention, I Witnesses claim as new anddesire to secure by Letters OHAs. H. SPRAGUE,

Patent--- '1. W. TRAVIS.

